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Slotted and unslotted transmissions

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• Slotted and unslotted transmissions
  • Slots and slotted transmissions:

    Slot (time slot) = the transmission time is divided into fixed size "slots" A transmission can only start at the begin of a slot:

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  • Unslotted transmission:

    In unslotted transmission, a transmission can start at any moment:

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• Slotted and unslotted transmission protocols
  • Slotted transmissions:

    A message that arrives during some slot t: will be transmitted in the slot t+1:

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  • Unslotted transmissions:

    A message that arrives: will be transmitted in the same time as its arrival moment:

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• Slotted and Unslotted Aloha
  • Slotted Aloha:

    Slotted Aloha = the Aloha network protocol that uses slotted transmissions

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  • Unslotted Aloha:

    Unslotted Aloha = the Aloha network protocol that uses unslotted transmissions